Norepinephrine enhances the LPS-induced expression of COX-2 and secretion of PGE2 in primary rat microglia

Background

Recent studies suggest an important role for neurotransmitters as modulators of inflammation. Neuroinflammatory mediators such as cytokines and molecules of the arachidonic acid pathway are generated and released by microglia. The monoamine norepinephrine reduces the production of cytokines by activated microglia in vitro. However, little is known about the effects of norepinephrine on prostanoid synthesis. In the present study, we investigate the role of norepinephrine on cyclooxygenase- (COX-)2 expression/synthesis and prostaglandin (PG)E₂ production in rat primary microglia.

Results

Interestingly, norepinephrine increased COX-2 mRNA, but not protein expression. Norepinephrine strongly enhanced COX-2 expression and PGE₂ production induced by lipopolysaccharide (LPS). This effect is likely to be mediated by β-adrenoreceptors, since β-, but not α-adrenoreceptor agonists produced similar results. Furthermore, β-adrenoreceptor antagonists blocked the enhancement of COX-2 levels induced by norepinephrine and β-adrenoreceptor agonists.

Conclusions

Considering that PGE₂ displays different roles in neuroinflammatory and neurodegenerative disorders, norepinephrine may play an important function in the modulation of these processes in pathophysiological conditions.

[Treatment of especially severe sex offenses]

"Therapy" is a currency with two different notations, as far as court practice is concerned. If the offences are of a minor nature, such as exhibitionism, the judge will usually expect the expert to mention the word, which prompts him to refer the delinquent to a therapist without delay, even if he is not at all hopeful that therapy may be successful. "Therapy" is an inflationary currency. In severe cases, its notation is correspondingly lower. This development has been promoted by the increasing division between forensic and therapeutic perspectives in psychiatry. The difficulties resulting therefore are discussed, taking the example of expertise and therapy of a patient accused of attempted murder as basis. Suggestions are advanced in what manner this division between forensic and therapeutic psychiatry could be avoided or even reduced in future.